wifi: mac80211: fix receiving mesh packets in forwarding=0 networks

When forwarding is set to 0, frames are typically sent with ttl=1.
Move the ttl decrement check below the check for local receive in order to
fix packet drops.

Reported-by: Thomas Hühn <thomas.huehn@hs-nordhausen.de>
Reported-by: Nick Hainke <vincent@systemli.org>
Fixes: 986e43b19ae9 ("wifi: mac80211: fix receiving A-MSDU frames on mesh interfaces")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20230326151709.17743-1-nbd@nbd.name
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index 7835189..7bd5aa2 100644 (file)
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2769,14 +2769,6 @@ ieee80211_rx_mesh_data(struct ieee80211_sub_if_data *sdata, struct sta_info *sta
        if (sdata->crypto_tx_tailroom_needed_cnt)
                tailroom = IEEE80211_ENCRYPT_TAILROOM;
 
-       if (!--mesh_hdr->ttl) {
-               if (multicast)
-                       goto rx_accept;
-
-               IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
-               return RX_DROP_MONITOR;
-       }
-
        if (mesh_hdr->flags & MESH_FLAGS_AE) {
                struct mesh_path *mppath;
                char *proxied_addr;
@@ -2807,6 +2799,14 @@ ieee80211_rx_mesh_data(struct ieee80211_sub_if_data *sdata, struct sta_info *sta
        if (ether_addr_equal(sdata->vif.addr, eth->h_dest))
                goto rx_accept;
 
+       if (!--mesh_hdr->ttl) {
+               if (multicast)
+                       goto rx_accept;
+
+               IEEE80211_IFSTA_MESH_CTR_INC(ifmsh, dropped_frames_ttl);
+               return RX_DROP_MONITOR;
+       }
+
        if (!ifmsh->mshcfg.dot11MeshForwarding) {
                if (is_multicast_ether_addr(eth->h_dest))
                        goto rx_accept;